FIFO PAGE REPLACEMENT ALGORITHM

• The simplest page replacement algorithm is a FIFO algorithm.
• The FIFO page replacement algorithm is easy to understand and program.
• problem:
• performance is not always good.
• bad replacement choice increases the page fault rate and slows process execution,but does not cause incorrect execution.
• A page fault is when a page is not present in a frame of memory so a trap has to be sent to the OS and the page has to be added to a frame. 
• FIFO queue is used to hold all pages in memory.
• replace the page at the head of the queue.
• When a page is brought into memory,insert it at the tail of the queue.
• If there is no room then something needs to be removed. 
• FIFO is one method to determine what page will get removed.
• The concept is that whatever page got added first to the frame will get removed first.
• This is what FIFO stands for. FIRST IN FIRST OUT.